Structured Packings
Structured packing was developed in the early 1940’s, but failed to be popular because of liquid maldistribution and a lack of sufficient markets. Afterwards, corrugated sheet type structured packing was developed in the late 1970’s, and now it is widely used.
Structured packing costs high and makes maintenance difficult. Especially, the drawback is that it is too vulnerable to fouling service. Despite this drawback, it is one of the most popular column internals today now that it has very low pressure loss and high performance. Additionally, it is also frequently used for vacuum towers where pressure loss should be very low; especially, it is mostly used for the revamp of conventional internals.